<!DOCTYPE html>
<html lang="en">

<head>
  <meta charset="UTF-8">
  <meta http-equiv="X-UA-Compatible" content="IE=edge">
  <meta name="viewport" content="width=device-width, initial-scale=1.0">
  <title>三角形</title>
  <style>
    .one {
      /* 设置div宽高 */
      width: 0;
      height: 0;
      /* transparent——透明 */
      border: 100px solid transparent;
      /* 设置下边框 */
      border-bottom: 100px solid plum;
    }

    .two {
      background-color: antiquewhite;
      width: 50px;
      height: 50px;
      /* border: 100px solid blue; */
      border-top: 100px solid rgb(110, 156, 187);
      border-left: 100px solid pink;
      border-right: 100px solid pink;
      border-bottom: 100px solid rgb(110, 156, 187);
    }
  </style>
</head>

<body>
  <div class="one"></div>
  <br>
  <br>
  <div class="two">测试</div>



</body>

</html>